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Abstract Particles containing alpha (α) nuclides were identified from sediment in stagnant water in the Unit 3 reactor building of the Fukushima Daiichi Nuclear Power Station (FDiNPS). We analyzed different concentrations of α-nuclide samples collected at two sampling sites, the torus room and the main steam isolation valve (MSIV) room. The solids in the stagnant water samples were classified, and the uranium (U) and total alpha concentrations of each fraction were measured by dissolution followed by inductively coupled plasma mass spectrometry and α-spectrometry. Most of the α-nuclides in the stagnant water samples from the torus and MSIV rooms were in particle fractions larger than 10 μm. We detected uranium-bearing particles ranging from sub-µm to 10 µm in size by scanning electron microscopy–energy-dispersive X-ray (SEM–EDX) observations. The chemical forms of U particles were determined in U–Zr oxides, oxidized UO2, and U3O8 with micro-Raman spectroscopy. Other short-lived α-nuclides (plutonium [Pu], americium [Am], and curium [Cm]) were detected by alpha track detection, and the particles with α-nuclides was characterized by SEM–EDX analysis. α-nuclide-containing particles with several tens to several 100 µm in size mainly comprised iron (Fe) oxyhydroxides. In addition, we detected adsorbed U onto Fe oxyhydroxide particles in the MSIV room sample, which indicated nuclear fuel dissolution and secondary U accumulation. This study clarifies the major characteristics of U and other α-nuclides in sediment in stagnant water in the FDiNPS Unit 3 reactor building, which significantly contribute to the consideration of removal methods for particles containing α-nuclides in the stagnant water.

Abstract Particles containing alpha (α) nuclides were identified from sediment in stagnant water in the torus room of the Fukushima Dai-ichi Nuclear Power Station(FDiNPS)’s Unit 2 reactor. We analyzed uranium (U), which is the main component of nuclear fuel, using scanning electron microscopy (SEM). Other α-nuclides (plutonium [Pu], americium [Am], and curium [Cm]) were detected by alpha track detection and the morphology of particles with α-nuclides were analyzed by SEM-energy dispersive X-Ray (EDX) analysis. Several uranium-bearing particles ranging from sub-µm to several µm in size were identified by SEM observation. These particles contained zirconium (Zr) and other elements which constituted fuel cladding and structural materials. The 235U/238U isotope ratio in the solid fractions that included U particles was consistent with what was found for the nuclear fuel in the Unit 2 reactor. This indicated that the U of similar fuel composition had made finer. The α-nuclide-containing particles identified by alpha track analysis were several tens to several hundred µm in size. The EDX spectra showed that these particles mainly comprised iron (Fe). Since the amount of α-nuclide material was very small, Pu, Am, and Cm were adsorbed on the Fe particles. This study clarifies that the major morphologies of U and other α-nuclides in the sediment of stagnant water in the torus room of FDiNPS’s Unit 2 reactor differed.

Abstract The Fukushima-Daiichi Nuclear Power Plant (FNPP) accident in March of 2011 released substantial amounts of radionuclides into the environment. We collected 4,957 deciduous teeth formed in children before the Fukushima accident to obtain precise control data for teeth formed after the accident. Radioactivity was measured using imaging plates (IP) and epidemiologically assessed using multivariate regression analysis. Additionally, we measured 90Sr, 137Cs, and natural radionuclides which might be present in teeth. Epidemiological studies of IP showed that the amount of radioactivity in teeth from Fukushima prefecture was similar to that from reference prefectures. We found that artificial radionuclides of 90Sr and 137Cs, which were believed to have originated from past nuclear disasters, and natural radionuclides including 40 K and daughter nuclides in the 238U and 232Th series contributed to the generation of radioactivity in teeth. We also found no evidence to suggest that radionuclides originating from the FNPP accident significantly contaminated pre-existing teeth. This is the first large-scale investigation of radioactivity and radionuclides in teeth. The present findings will be indispensable for future studies of teeth formed after the FNPP accident, which will fall out over the next several years and might be more contaminated with radionuclides.

Skeletons of hermatypic corals (e.g., Porites) might have enormous potential as a high-resolution paleomagnetic recorder owing to their rapid and continuous growth over hundreds of years at a rate of up to 2 cm/year, although typical corals show an extremely weak intensity of remanence and low stability. We found that coral tsunami boulders with negligible amounts of calcite on Ishigaki Island show a measurable intensity of remanence; thus, we attempted to characterize the magnetic assemblages in this coral skeleton to determine whether it is of biogenic or detrital magnetite using first-order reversal curve (FORC) measurements, ferromagnetic resonance (FMR) spectroscopy, and petrological observations through field-emission type scanning electron microscope (FE-SEM) with an acid treatment. The FMR derivative spectra of coral skeleton samples represent multiple derivative maxima and extended low-field absorption, indicating the presence of intact biogenic magnetite chains. FORC diagrams represent a “central ridge„ signature with a vertical spread. These FMR and FORC features indicate the magnetization of these coral skeletons that are mainly created using intact biogenic magnetites and mixtures of grains from collapsed biogenic magnetites, pseudo-single domain grains, and multi-domain grains such as detrital magnetite. FE-SEM observations confirm the presence of a chain-like structure of iron oxides corresponding to the features of biogenic magnetite. Therefore, the magnetic mineral assemblage in coralline boulders from Ishigaki Island consists of dominant biogenic-origin single-domain magnetite and a trace amount of detrital component, indicating that fossil coral skeletons in Ishigaki Island have potential for utilization in paleomagnetic studies.

Key Clinical Message We should consider IgG4‐related disease (IGRD) as one of the potential causes of constrictive pericarditis. In patients with constrictive pericarditis due to IGRD, the combination of surgical treatment and immunosuppressive therapy may be an effective strategy.

Electron spin resonance (ESR) dating of a fault is a developing technology with the potential to di- rectly determine the age of the last seismic fault slip. This method assumes that charge trapping centers in quartz in a fault material have been completely annihilated by the seismic fault slip (ESR signal zeroing) [1]. To date, there is very little understanding of the relationship between the signal zeroing and seismic slip parameters of faults. The previous high-velocity friction (HVF) experiments have implied that the E1' center (an unpaired electron trapped in an oxygen vacancy [2]) in quartz detected by ESR measurement could be correlated with frictional power density and begin to decrease due to frictional heating at a power density of 0.6-0.9 MW/m² [3]. However, the data was lacking to confirm the signal zeroing at higher power density corresponding to the seismic slips of large earthquakes. This study aims to quantitatively assess the relationship between the E1' center and larger frictional power density by HVF experiments. We performed HVF experiments for simulated quartz gouges with an equivalent slip rate of 1 m/s, an equivalent displacement of 10 m, and normal stresses of 1.0-2.5 MPa. The temperature during the expe-riment was measured with thermocouples installed in the stationary cylinder, less than a few millimeters from the sliding surface. For gouges before and after experiments, ESR measurements to detect the E1' center were conducted. The peak-to-peak height at g value ≈ 2.001 of the E1' center calibrated by that of the standard material was calculated as the ESR intensity (ESR intensity ratio) of the E1' center. In the HVF experiments, the ESR intensity ratio of the E1' center decreased with increasing frictional power density of 0.96-1.4 MW/m2 at normal stresses of 1.0-2.5 MPa. The observed maximum tempera- tures were 260°C at 0.96 MW/m² (1.0 MPa), 600°C at 1.0 MW/m³ (1.5 MPa), and 480°C at 1.6 MW/m² (2.5 MPa). The E1' center is thermally unstable at ≥300°C and more unstable at higher temperatures [4]. Hence, the ESR intensity ratio might decrease due to larger frictional heating with increasing frictional power density. Comparing our results with those in the previous study, the ESR intensity ratio clearly decreased with increasing frictional power densities of 0.6-1.4 MW/m². It suggests that the ESR intensity ratio of the E1' center turns to decrease from a frictional power density at about 0.6 MW/m² and can drop to zero at a larger frictional power density. The HVF experiments in this study mimic seismic fault slips induced by earthquakes with a moment magnitude of 8-9 at shallow depths of ≤100 m. Seismic fault slip associated with an earthquake at a depth of at least one hundred meters beneath the earth's surface can be required for ESR signal zeroing of charge trapping centers, particularly the E1' center. [ABSTRACT FROM AUTHOR]

Abstract Aims Our purpose was to investigate the association between the B‐type natriuretic peptide (BNP) level at discharge, the occurrence of worsening renal function (WRF), and long‐term outcomes in patients with heart failure (HF). Methods and results We enrolled hospitalized acute HF patients. We divided patients into four groups on the basis of BNP

Free volume of polystyrene films treated with supercritical carbon dioxide (SCCO 2) were examined by positron annihilation lifetime spectroscopy. Variation of the free volume sizes after the SCCO 2treatment due to the release of trapped CO 2and structural relaxation of the polymer was observed. After 500 h from the depressurization, the free volume of the treated films free from CO 2was ∼0.306 nm in radius and much larger than that of the untreated films of ∼0.295 nm in radius due to the freezing of the swollen structure caused by the large solubility of CO 2. [ABSTRACT FROM AUTHOR]

Nanoporous polysiloxane films were fabricated by plasma polymerization of hexamethyldisiloxane mixed with cyclohexane under different conditions. The pores were generated through the elimination of carbonaceous aggregates (porogen) by annealing at 600 °C. Results of spectroscopic ellipsometry, Fourier transform infrared spectroscopy, and positron annihilation lifetime spectroscopy suggest that not only film porosity but also average pore size depends on the amount of the decomposable porogen. The pore size was controllable in a range between 0.6 and 1.0 nm in radius by proper selection of the substrate temperature and precursor composition. [ABSTRACT FROM AUTHOR]

INTRODUCTION:There were few studies that investigated the association between serum zinc concentration and acute myocardial infarction (AMI) in percutaneous coronary intervention era. OBJECTIVE:We assessed the relationships between serum zinc concentration, complications, and prognosis in AMI patients after primary percutaneous coronary intervention. METHODS:We conducted a single-center, prospective, observational study including 50 patients with AMI. We divided patients into two groups (High-zinc group and Low-zinc group) by median serum zinc concentration and compared two groups about clinical outcomes up to 1 year follow up. RESULTS:The mean age of patients was 66.2 ± 11.8 years old. Patients in the Low-zinc group had ST-segment elevation more frequently than those in the High-zinc group (96.0% vs. 72.0%, P = 0.02). All-cause mortality at 1 year was similar in both groups (P (log-rank) = 0.33). However, the lengths of hospital stay and in coronary care unit were longer in patients in the Low-zinc group than in those in the High-zinc group (15.6 ± 9.2 days vs. 11.9 ± 2.9 days, P = 0.06; 3.9 ± 2.8 days vs. 2.3 ± 0.8 days, P = 0.01). Multivariate regression analysis showed that low serum zinc concentration was associated with the use of cardiac or respiratory assist devices (adjusted odds ratio, 17.79; 95% CI 1.123 to 1216.5; P = 0.04). CONCLUSIONS:Although there was no significance difference in mortality in Low-zinc and High-zinc groups, low serum zinc concentration was associated with longer stay in the coronary care unit, and was one of the independent predictors for the use of cardiac or respiratory assist devices.

Nanoimprint lithography has been applied to the manufacture of microlenses, antireflection films, and biochips because of its cost reduction advantage. Previously, we demonstrated a gas-permeable template derived from a thermal cross-linkable cellulose derivative with methacrylate (HPC-MOI) that eliminated defects due to the concentration of acetone gas between the template and the imprint material. In this study, we prepared a thermoset cellulose derivative with acrylate as the gas-permeable template (HPC-AOI). The results of Raman spectroscopy and indentation test confirmed that HPC-AOI had a very high cross-linking density when heated for 10 min. The micrographs and three-dimensional (3D) image of the 5 µm line and space pattern in the UV cross-linked material containing a volatile solvent showed that void defects were removed and edges were sharper when the HPC-AOI template was utilized. [ABSTRACT FROM AUTHOR]

BACKGROUND: Gene transduction has been considered advantageous for the sustained delivery of proteins to specific target tissues. However, in the case of hard tissues, such as bone, local gene delivery remains problematic owing to anatomical accessibility limitations of the target sites. METHODOLOGY/PRINCIPAL FINDINGS: Here, we evaluated the feasibility of exogenous gene transduction in the interior of bone via axonal transport following intramuscular administration of a nonviral vector. A high expression level of the transduced gene was achieved in the tibia ipsilateral to the injected tibialis anterior muscle, as well as in the ipsilateral sciatic nerve and dorsal root ganglia. In sciatic transection rats, the gene expression level was significantly lowered in bone. CONCLUSIONS/SIGNIFICANCE: These results suggest that axonal transport is critical for gene transduction. Our study may provide a basis for developing therapeutic methods for efficient gene delivery into hard tissues.